deploy: current vibn theia state

Made-with: Cursor

packages/filesystem/src/node/disk-file-system-provider.ts

@@ -0,0 +1,914 @@
+// *****************************************************************************
+// Copyright (C) 2020 TypeFox and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+// based on https://github.com/microsoft/vscode/blob/04c36be045a94fee58e5f8992d3e3fd980294a84/src/vs/platform/files/node/diskFileSystemProvider.ts
+
+/* eslint-disable no-null/no-null */
+/* eslint-disable @typescript-eslint/no-shadow */
+
+import { injectable, inject, postConstruct } from '@theia/core/shared/inversify';
+import { basename, dirname, normalize, join } from 'path';
+import { generateUuid } from '@theia/core/lib/common/uuid';
+import * as os from 'os';
+import * as fs from 'fs';
+import {
+    mkdir, open, close, read, write, fdatasync, Stats,
+    lstat, stat, readdir, readFile, exists, chmod,
+    rmdir, unlink, rename, futimes, truncate
+} from 'fs';
+import { promisify } from 'util';
+import URI from '@theia/core/lib/common/uri';
+import { Path } from '@theia/core/lib/common/path';
+import { FileUri } from '@theia/core/lib/common/file-uri';
+import { Event, Emitter } from '@theia/core/lib/common/event';
+import { Disposable, DisposableCollection } from '@theia/core/lib/common/disposable';
+import { OS, isWindows } from '@theia/core/lib/common/os';
+import { retry } from '@theia/core/lib/common/promise-util';
+import {
+    FileSystemProviderWithFileReadWriteCapability, FileSystemProviderWithOpenReadWriteCloseCapability, FileSystemProviderWithFileFolderCopyCapability,
+    FileSystemProviderCapabilities,
+    Stat,
+    FileType,
+    FileWriteOptions,
+    createFileSystemProviderError,
+    FileSystemProviderErrorCode,
+    FileOpenOptions,
+    FileDeleteOptions,
+    FileOverwriteOptions,
+    FileSystemProviderError,
+    FileChange,
+    WatchOptions,
+    FileUpdateOptions, FileUpdateResult, FileReadStreamOptions, FilePermission
+} from '../common/files';
+import { FileSystemWatcherServer } from '../common/filesystem-watcher-protocol';
+import trash = require('trash');
+import { TextDocumentContentChangeEvent } from '@theia/core/shared/vscode-languageserver-protocol';
+import { TextDocument } from 'vscode-languageserver-textdocument';
+import { EncodingService } from '@theia/core/lib/common/encoding-service';
+import { BinaryBuffer } from '@theia/core/lib/common/buffer';
+import { ReadableStreamEvents, newWriteableStream } from '@theia/core/lib/common/stream';
+import { CancellationToken } from '@theia/core/lib/common/cancellation';
+import { readFileIntoStream } from '../common/io';
+import { Mode } from 'stat-mode';
+
+export namespace DiskFileSystemProvider {
+    export interface StatAndLink {
+
+        // The stats of the file. If the file is a symbolic
+        // link, the stats will be of that target file and
+        // not the link itself.
+        // If the file is a symbolic link pointing to a non
+        // existing file, the stat will be of the link and
+        // the `dangling` flag will indicate this.
+        stat: fs.Stats;
+
+        // Will be provided if the resource is a symbolic link
+        // on disk. Use the `dangling` flag to find out if it
+        // points to a resource that does not exist on disk.
+        symbolicLink?: { dangling: boolean };
+    }
+}
+
+@injectable()
+export class DiskFileSystemProvider implements Disposable,
+    FileSystemProviderWithFileReadWriteCapability,
+    FileSystemProviderWithOpenReadWriteCloseCapability,
+    FileSystemProviderWithFileFolderCopyCapability {
+
+    private readonly BUFFER_SIZE = 64 * 1024;
+
+    private readonly onDidChangeFileEmitter = new Emitter<readonly FileChange[]>();
+    readonly onDidChangeFile = this.onDidChangeFileEmitter.event;
+
+    private readonly onFileWatchErrorEmitter = new Emitter<void>();
+    readonly onFileWatchError = this.onFileWatchErrorEmitter.event;
+
+    protected readonly toDispose = new DisposableCollection(
+        this.onDidChangeFileEmitter
+    );
+
+    @inject(FileSystemWatcherServer)
+    protected readonly watcher: FileSystemWatcherServer;
+
+    @inject(EncodingService)
+    protected readonly encodingService: EncodingService;
+
+    @postConstruct()
+    protected init(): void {
+        this.toDispose.push(this.watcher);
+        this.watcher.setClient({
+            onDidFilesChanged: params => this.onDidChangeFileEmitter.fire(params.changes.map(({ uri, type }) => ({
+                resource: new URI(uri),
+                type
+            }))),
+            onError: () => this.onFileWatchErrorEmitter.fire()
+        });
+    }
+
+    // #region File Capabilities
+
+    readonly onDidChangeCapabilities = Event.None;
+
+    protected _capabilities: FileSystemProviderCapabilities | undefined;
+    get capabilities(): FileSystemProviderCapabilities {
+        if (!this._capabilities) {
+            this._capabilities =
+                FileSystemProviderCapabilities.FileReadWrite |
+                FileSystemProviderCapabilities.FileOpenReadWriteClose |
+                FileSystemProviderCapabilities.FileReadStream |
+                FileSystemProviderCapabilities.FileFolderCopy |
+                FileSystemProviderCapabilities.Access |
+                FileSystemProviderCapabilities.Trash |
+                FileSystemProviderCapabilities.Update;
+
+            if (OS.type() === OS.Type.Linux) {
+                this._capabilities |= FileSystemProviderCapabilities.PathCaseSensitive;
+            }
+        }
+
+        return this._capabilities;
+    }
+
+    // #endregion
+
+    // #region File Metadata Resolving
+
+    async stat(resource: URI): Promise<Stat> {
+        try {
+            const { stat, symbolicLink } = await this.statLink(this.toFilePath(resource)); // cannot use fs.stat() here to support links properly
+            const mode = new Mode(stat);
+            return {
+                type: this.toType(stat, symbolicLink),
+                ctime: stat.birthtime.getTime(), // intentionally not using ctime here, we want the creation time
+                mtime: stat.mtime.getTime(),
+                size: stat.size,
+                permissions: !mode.owner.write ? FilePermission.Readonly : undefined,
+            };
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    async access(resource: URI, mode?: number): Promise<void> {
+        try {
+            await promisify(fs.access)(this.toFilePath(resource), mode);
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    async fsPath(resource: URI): Promise<string> {
+        return FileUri.fsPath(resource);
+    }
+
+    protected async statLink(path: string): Promise<DiskFileSystemProvider.StatAndLink> {
+
+        // First stat the link
+        let lstats: Stats | undefined;
+        try {
+            lstats = await promisify(lstat)(path);
+
+            // Return early if the stat is not a symbolic link at all
+            if (!lstats.isSymbolicLink()) {
+                return { stat: lstats };
+            }
+        } catch (error) {
+            /* ignore - use stat() instead */
+        }
+
+        // If the stat is a symbolic link or failed to stat, use fs.stat()
+        // which for symbolic links will stat the target they point to
+        try {
+            const stats = await promisify(stat)(path);
+
+            return { stat: stats, symbolicLink: lstats?.isSymbolicLink() ? { dangling: false } : undefined };
+        } catch (error) {
+
+            // If the link points to a non-existing file we still want
+            // to return it as result while setting dangling: true flag
+            if (error.code === 'ENOENT' && lstats) {
+                return { stat: lstats, symbolicLink: { dangling: true } };
+            }
+
+            throw error;
+        }
+    }
+
+    async readdir(resource: URI): Promise<[string, FileType][]> {
+        try {
+            const children = await promisify(fs.readdir)(this.toFilePath(resource));
+
+            const result: [string, FileType][] = [];
+            await Promise.all(children.map(async child => {
+                try {
+                    const stat = await this.stat(resource.resolve(child));
+                    result.push([child, stat.type]);
+                } catch (error) {
+                    console.trace(error); // ignore errors for individual entries that can arise from permission denied
+                }
+            }));
+
+            return result;
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    private toType(entry: Stats, symbolicLink?: { dangling: boolean }): FileType {
+        // Signal file type by checking for file / directory, except:
+        // - symbolic links pointing to non-existing files are FileType.Unknown
+        // - files that are neither file nor directory are FileType.Unknown
+        let type: FileType;
+        if (symbolicLink?.dangling) {
+            type = FileType.Unknown;
+        } else if (entry.isFile()) {
+            type = FileType.File;
+        } else if (entry.isDirectory()) {
+            type = FileType.Directory;
+        } else {
+            type = FileType.Unknown;
+        }
+
+        // Always signal symbolic link as file type additionally
+        if (symbolicLink) {
+            type |= FileType.SymbolicLink;
+        }
+
+        return type;
+    }
+
+    // #endregion
+
+    // #region File Reading/Writing
+
+    async readFile(resource: URI): Promise<Uint8Array> {
+        try {
+            const filePath = this.toFilePath(resource);
+
+            return await promisify(readFile)(filePath);
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    readFileStream(resource: URI, opts: FileReadStreamOptions, token: CancellationToken): ReadableStreamEvents<Uint8Array> {
+        const stream = newWriteableStream<Uint8Array>(data => BinaryBuffer.concat(data.map(data => BinaryBuffer.wrap(data))).buffer);
+
+        readFileIntoStream(this, resource, stream, data => data.buffer, {
+            ...opts,
+            bufferSize: this.BUFFER_SIZE
+        }, token);
+
+        return stream;
+    }
+
+    async writeFile(resource: URI, content: Uint8Array, opts: FileWriteOptions): Promise<void> {
+        let handle: number | undefined = undefined;
+        try {
+            const filePath = this.toFilePath(resource);
+
+            // Validate target unless { create: true, overwrite: true }
+            if (!opts.create || !opts.overwrite) {
+                const fileExists = await promisify(exists)(filePath);
+
+                if (fileExists) {
+                    if (!opts.overwrite) {
+                        throw createFileSystemProviderError('File already exists', FileSystemProviderErrorCode.FileExists);
+                    }
+                } else if (!opts.create) {
+                    throw createFileSystemProviderError('File does not exist', FileSystemProviderErrorCode.FileNotFound);
+                }
+            }
+
+            // Open
+            handle = await this.open(resource, { create: true });
+
+            // Write content at once
+            await this.write(handle, 0, content, 0, content.byteLength);
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        } finally {
+            if (typeof handle === 'number') {
+                await this.close(handle);
+            }
+        }
+    }
+
+    private mapHandleToPos: Map<number, number> = new Map();
+
+    private writeHandles: Set<number> = new Set();
+    private canFlush: boolean = true;
+
+    async open(resource: URI, opts: FileOpenOptions): Promise<number> {
+        try {
+            const filePath = this.toFilePath(resource);
+
+            let flags: string | undefined = undefined;
+            if (opts.create) {
+                if (isWindows && await promisify(exists)(filePath)) {
+                    try {
+                        // On Windows and if the file exists, we use a different strategy of saving the file
+                        // by first truncating the file and then writing with r+ flag. This helps to save hidden files on Windows
+                        // (see https://github.com/Microsoft/vscode/issues/931) and prevent removing alternate data streams
+                        // (see https://github.com/Microsoft/vscode/issues/6363)
+                        await promisify(truncate)(filePath, 0);
+
+                        // After a successful truncate() the flag can be set to 'r+' which will not truncate.
+                        flags = 'r+';
+                    } catch (error) {
+                        console.trace(error);
+                    }
+                }
+
+                // we take opts.create as a hint that the file is opened for writing
+                // as such we use 'w' to truncate an existing or create the
+                // file otherwise. we do not allow reading.
+                if (!flags) {
+                    flags = 'w';
+                }
+            } else {
+                // otherwise we assume the file is opened for reading
+                // as such we use 'r' to neither truncate, nor create
+                // the file.
+                flags = 'r';
+            }
+
+            const handle = await promisify(open)(filePath, flags);
+
+            // remember this handle to track file position of the handle
+            // we init the position to 0 since the file descriptor was
+            // just created and the position was not moved so far (see
+            // also http://man7.org/linux/man-pages/man2/open.2.html -
+            // "The file offset is set to the beginning of the file.")
+            this.mapHandleToPos.set(handle, 0);
+
+            // remember that this handle was used for writing
+            if (opts.create) {
+                this.writeHandles.add(handle);
+            }
+
+            return handle;
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    async close(fd: number): Promise<void> {
+        try {
+
+            // remove this handle from map of positions
+            this.mapHandleToPos.delete(fd);
+
+            // if a handle is closed that was used for writing, ensure
+            // to flush the contents to disk if possible.
+            if (this.writeHandles.delete(fd) && this.canFlush) {
+                try {
+                    await promisify(fdatasync)(fd);
+                } catch (error) {
+                    // In some exotic setups it is well possible that node fails to sync
+                    // In that case we disable flushing and log the error to our logger
+                    this.canFlush = false;
+                    console.error(error);
+                }
+            }
+
+            return await promisify(close)(fd);
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    async read(fd: number, pos: number, data: Uint8Array, offset: number, length: number): Promise<number> {
+        const normalizedPos = this.normalizePos(fd, pos);
+
+        let bytesRead: number | null = null;
+        try {
+            const result = await promisify(read)(fd, data, offset, length, normalizedPos);
+
+            if (typeof result === 'number') {
+                bytesRead = result; // node.d.ts fail
+            } else {
+                bytesRead = result.bytesRead;
+            }
+
+            return bytesRead;
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        } finally {
+            this.updatePos(fd, normalizedPos, bytesRead);
+        }
+    }
+
+    private normalizePos(fd: number, pos: number): number | null {
+
+        // when calling fs.read/write we try to avoid passing in the "pos" argument and
+        // rather prefer to pass in "null" because this avoids an extra seek(pos)
+        // call that in some cases can even fail (e.g. when opening a file over FTP -
+        // see https://github.com/microsoft/vscode/issues/73884).
+        //
+        // as such, we compare the passed in position argument with our last known
+        // position for the file descriptor and use "null" if they match.
+        if (pos === this.mapHandleToPos.get(fd)) {
+            return null;
+        }
+
+        return pos;
+    }
+
+    private updatePos(fd: number, pos: number | null, bytesLength: number | null): void {
+        const lastKnownPos = this.mapHandleToPos.get(fd);
+        if (typeof lastKnownPos === 'number') {
+
+            // pos !== null signals that previously a position was used that is
+            // not null. node.js documentation explains, that in this case
+            // the internal file pointer is not moving and as such we do not move
+            // our position pointer.
+            //
+            // Docs: "If position is null, data will be read from the current file position,
+            // and the file position will be updated. If position is an integer, the file position
+            // will remain unchanged."
+            if (typeof pos === 'number') {
+                // do not modify the position
+            } else if (typeof bytesLength === 'number') {
+                this.mapHandleToPos.set(fd, lastKnownPos + bytesLength);
+            } else {
+                this.mapHandleToPos.delete(fd);
+            }
+        }
+    }
+
+    async write(fd: number, pos: number, data: Uint8Array, offset: number, length: number): Promise<number> {
+        // we know at this point that the file to write to is truncated and thus empty
+        // if the write now fails, the file remains empty. as such we really try hard
+        // to ensure the write succeeds by retrying up to three times.
+        return retry(() => this.doWrite(fd, pos, data, offset, length), 100 /* ms delay */, 3 /* retries */);
+    }
+
+    private async doWrite(fd: number, pos: number, data: Uint8Array, offset: number, length: number): Promise<number> {
+        const normalizedPos = this.normalizePos(fd, pos);
+
+        let bytesWritten: number | null = null;
+        try {
+            const result = await promisify(write)(fd, data, offset, length, normalizedPos);
+
+            if (typeof result === 'number') {
+                bytesWritten = result; // node.d.ts fail
+            } else {
+                bytesWritten = result.bytesWritten;
+            }
+
+            return bytesWritten;
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        } finally {
+            this.updatePos(fd, normalizedPos, bytesWritten);
+        }
+    }
+
+    // #endregion
+
+    // #region Move/Copy/Delete/Create Folder
+
+    async mkdir(resource: URI): Promise<void> {
+        try {
+            await promisify(mkdir)(this.toFilePath(resource));
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    async delete(resource: URI, opts: FileDeleteOptions): Promise<void> {
+        try {
+            const filePath = this.toFilePath(resource);
+
+            await this.doDelete(filePath, opts);
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    protected async doDelete(filePath: string, opts: FileDeleteOptions): Promise<void> {
+        if (!opts.useTrash) {
+            if (opts.recursive) {
+                await this.rimraf(filePath);
+            } else {
+                const stat = await promisify(lstat)(filePath);
+                if (stat.isDirectory() && !stat.isSymbolicLink()) {
+                    await promisify(rmdir)(filePath);
+                } else {
+                    await promisify(unlink)(filePath);
+                }
+            }
+        } else {
+            await trash(filePath);
+        }
+    }
+
+    protected rimraf(path: string): Promise<void> {
+        if (new Path(path).isRoot) {
+            throw new Error('rimraf - will refuse to recursively delete root');
+        }
+        return this.rimrafMove(path);
+    }
+
+    protected async rimrafMove(path: string): Promise<void> {
+        try {
+            const pathInTemp = join(os.tmpdir(), generateUuid());
+            try {
+                await promisify(rename)(path, pathInTemp);
+            } catch (error) {
+                return this.rimrafUnlink(path); // if rename fails, delete without tmp dir
+            }
+
+            // Delete but do not return as promise
+            this.rimrafUnlink(pathInTemp);
+        } catch (error) {
+            if (error.code !== 'ENOENT') {
+                throw error;
+            }
+        }
+    }
+
+    protected async rimrafUnlink(path: string): Promise<void> {
+        try {
+            const stat = await promisify(lstat)(path);
+
+            // Folder delete (recursive) - NOT for symbolic links though!
+            if (stat.isDirectory() && !stat.isSymbolicLink()) {
+
+                // Children
+                const children = await promisify(readdir)(path);
+                await Promise.all(children.map(child => this.rimrafUnlink(join(path, child))));
+
+                // Folder
+                await promisify(rmdir)(path);
+            } else {
+
+                // chmod as needed to allow for unlink
+                const mode = stat.mode;
+                if (!(mode & 128)) { // 128 === 0200
+                    await promisify(chmod)(path, mode | 128);
+                }
+
+                return promisify(unlink)(path);
+            }
+        } catch (error) {
+            if (error.code !== 'ENOENT') {
+                throw error;
+            }
+        }
+    }
+
+    async rename(from: URI, to: URI, opts: FileOverwriteOptions): Promise<void> {
+        const fromFilePath = this.toFilePath(from);
+        const toFilePath = this.toFilePath(to);
+
+        if (fromFilePath === toFilePath) {
+            return; // simulate node.js behaviour here and do a no-op if paths match
+        }
+
+        try {
+
+            // Ensure target does not exist
+            await this.validateTargetDeleted(from, to, 'move', opts.overwrite);
+
+            // Move
+            await this.move(fromFilePath, toFilePath);
+        } catch (error) {
+
+            // rewrite some typical errors that can happen especially around symlinks
+            // to something the user can better understand
+            if (error.code === 'EINVAL' || error.code === 'EBUSY' || error.code === 'ENAMETOOLONG') {
+                error = new Error(`Unable to move '${basename(fromFilePath)}' into '${basename(dirname(toFilePath))}' (${error.toString()}).`);
+            }
+
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    protected async move(source: string, target: string): Promise<void> {
+        if (source === target) {
+            return Promise.resolve();
+        }
+
+        async function updateMtime(path: string): Promise<void> {
+            const stat = await promisify(lstat)(path);
+            if (stat.isDirectory() || stat.isSymbolicLink()) {
+                return Promise.resolve(); // only for files
+            }
+
+            const fd = await promisify(open)(path, 'a');
+            try {
+                await promisify(futimes)(fd, stat.atime, new Date());
+            } catch (error) {
+                // ignore
+            }
+
+            return promisify(close)(fd);
+        }
+
+        try {
+            await promisify(rename)(source, target);
+            await updateMtime(target);
+        } catch (error) {
+
+            // In two cases we fallback to classic copy and delete:
+            //
+            // 1.) The EXDEV error indicates that source and target are on different devices
+            // In this case, fallback to using a copy() operation as there is no way to
+            // rename() between different devices.
+            //
+            // 2.) The user tries to rename a file/folder that ends with a dot. This is not
+            // really possible to move then, at least on UNC devices.
+            if (source.toLowerCase() !== target.toLowerCase() && error.code === 'EXDEV' || source.endsWith('.')) {
+                await this.doCopy(source, target);
+                await this.rimraf(source);
+                await updateMtime(target);
+            } else {
+                throw error;
+            }
+        }
+    }
+
+    async copy(from: URI, to: URI, opts: FileOverwriteOptions): Promise<void> {
+        const fromFilePath = this.toFilePath(from);
+        const toFilePath = this.toFilePath(to);
+
+        if (fromFilePath === toFilePath) {
+            return; // simulate node.js behaviour here and do a no-op if paths match
+        }
+
+        try {
+
+            // Ensure target does not exist
+            await this.validateTargetDeleted(from, to, 'copy', opts.overwrite);
+
+            // Copy
+            await this.doCopy(fromFilePath, toFilePath);
+        } catch (error) {
+
+            // rewrite some typical errors that can happen especially around symlinks
+            // to something the user can better understand
+            if (error.code === 'EINVAL' || error.code === 'EBUSY' || error.code === 'ENAMETOOLONG') {
+                error = new Error(`Unable to copy '${basename(fromFilePath)}' into '${basename(dirname(toFilePath))}' (${error.toString()}).`);
+            }
+
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    private async validateTargetDeleted(from: URI, to: URI, mode: 'move' | 'copy', overwrite?: boolean): Promise<void> {
+        const isPathCaseSensitive = !!(this.capabilities & FileSystemProviderCapabilities.PathCaseSensitive);
+
+        const fromFilePath = this.toFilePath(from);
+        const toFilePath = this.toFilePath(to);
+
+        let isSameResourceWithDifferentPathCase = false;
+        if (!isPathCaseSensitive) {
+            isSameResourceWithDifferentPathCase = fromFilePath.toLowerCase() === toFilePath.toLowerCase();
+        }
+
+        if (isSameResourceWithDifferentPathCase && mode === 'copy') {
+            throw createFileSystemProviderError("'File cannot be copied to same path with different path case", FileSystemProviderErrorCode.FileExists);
+        }
+
+        // handle existing target (unless this is a case change)
+        if (!isSameResourceWithDifferentPathCase && await promisify(exists)(toFilePath)) {
+            if (!overwrite) {
+                throw createFileSystemProviderError('File at target already exists', FileSystemProviderErrorCode.FileExists);
+            }
+
+            // Delete target
+            await this.delete(to, { recursive: true, useTrash: false });
+        }
+    }
+
+    protected async doCopy(source: string, target: string, copiedSourcesIn?: { [path: string]: boolean }): Promise<void> {
+        const copiedSources = copiedSourcesIn ? copiedSourcesIn : Object.create(null);
+
+        const fileStat = await promisify(stat)(source);
+        if (!fileStat.isDirectory()) {
+            return this.doCopyFile(source, target, fileStat.mode & 511);
+        }
+
+        if (copiedSources[source]) {
+            return Promise.resolve(); // escape when there are cycles (can happen with symlinks)
+        }
+
+        copiedSources[source] = true; // remember as copied
+
+        // Create folder
+        await this.mkdirp(target, fileStat.mode & 511);
+
+        // Copy each file recursively
+        const files = await promisify(readdir)(source);
+        for (let i = 0; i < files.length; i++) {
+            const file = files[i];
+            await this.doCopy(join(source, file), join(target, file), copiedSources);
+        }
+    }
+
+    protected async mkdirp(path: string, mode?: number): Promise<void> {
+        const mkdir = async () => {
+            try {
+                await promisify(fs.mkdir)(path, mode);
+            } catch (error) {
+
+                // ENOENT: a parent folder does not exist yet
+                if (error.code === 'ENOENT') {
+                    throw error;
+                }
+
+                // Any other error: check if folder exists and
+                // return normally in that case if its a folder
+                let targetIsFile = false;
+                try {
+                    const fileStat = await promisify(fs.stat)(path);
+                    targetIsFile = !fileStat.isDirectory();
+                } catch (statError) {
+                    throw error; // rethrow original error if stat fails
+                }
+
+                if (targetIsFile) {
+                    throw new Error(`'${path}' exists and is not a directory.`);
+                }
+            }
+        };
+
+        // stop at root
+        if (path === dirname(path)) {
+            return;
+        }
+
+        try {
+            await mkdir();
+        } catch (error) {
+
+            // ENOENT: a parent folder does not exist yet, continue
+            // to create the parent folder and then try again.
+            if (error.code === 'ENOENT') {
+                await this.mkdirp(dirname(path), mode);
+
+                return mkdir();
+            }
+
+            // Any other error
+            throw error;
+        }
+    }
+
+    protected doCopyFile(source: string, target: string, mode: number): Promise<void> {
+        return new Promise((resolve, reject) => {
+            const reader = fs.createReadStream(source);
+            const writer = fs.createWriteStream(target, { mode });
+
+            let finished = false;
+            const finish = (error?: Error) => {
+                if (!finished) {
+                    finished = true;
+
+                    // in error cases, pass to callback
+                    if (error) {
+                        return reject(error);
+                    }
+
+                    // we need to explicitly chmod because of https://github.com/nodejs/node/issues/1104
+                    fs.chmod(target, mode, error => error ? reject(error) : resolve());
+                }
+            };
+
+            // handle errors properly
+            reader.once('error', error => finish(error));
+            writer.once('error', error => finish(error));
+
+            // we are done (underlying fd has been closed)
+            writer.once('close', () => finish());
+
+            // start piping
+            reader.pipe(writer);
+        });
+    }
+
+    // #endregion
+
+    // #region File Watching
+
+    watch(resource: URI, opts: WatchOptions): Disposable {
+        const watcherService = this.watcher;
+        /**
+         * Disposable handle. Can be disposed early (before the watcher is allocated.)
+         */
+        const handle = {
+            disposed: false,
+            watcherId: undefined as number | undefined,
+            dispose(): void {
+                if (this.disposed) {
+                    return;
+                }
+                if (this.watcherId !== undefined) {
+                    watcherService.unwatchFileChanges(this.watcherId);
+                }
+                this.disposed = true;
+            },
+        };
+        watcherService.watchFileChanges(resource.toString(), {
+            // Convert from `files.WatchOptions` to internal `watcher-protocol.WatchOptions`:
+            ignored: opts.excludes
+        }).then(watcherId => {
+            if (handle.disposed) {
+                watcherService.unwatchFileChanges(watcherId);
+            } else {
+                handle.watcherId = watcherId;
+            }
+        });
+        this.toDispose.push(handle);
+        return handle;
+    }
+
+    // #endregion
+
+    async updateFile(resource: URI, changes: TextDocumentContentChangeEvent[], opts: FileUpdateOptions): Promise<FileUpdateResult> {
+        try {
+            const content = await this.readFile(resource);
+            const decoded = this.encodingService.decode(BinaryBuffer.wrap(content), opts.readEncoding);
+            const newContent = TextDocument.update(TextDocument.create('', '', 1, decoded), changes, 2).getText();
+            const encoding = await this.encodingService.toResourceEncoding(opts.writeEncoding, {
+                overwriteEncoding: opts.overwriteEncoding,
+                read: async length => {
+                    const fd = await this.open(resource, { create: false });
+                    try {
+                        const data = new Uint8Array(length);
+                        await this.read(fd, 0, data, 0, length);
+                        return data;
+                    } finally {
+                        await this.close(fd);
+                    }
+                }
+            });
+            const encoded = this.encodingService.encode(newContent, encoding);
+            await this.writeFile(resource, encoded.buffer, { create: false, overwrite: true });
+            const stat = await this.stat(resource);
+            return Object.assign(stat, { encoding: encoding.encoding });
+        } catch (error) {
+            throw this.toFileSystemProviderError(error);
+        }
+    }
+
+    // #region Helpers
+
+    protected toFilePath(resource: URI): string {
+        return normalize(FileUri.fsPath(resource));
+    }
+
+    private toFileSystemProviderError(error: NodeJS.ErrnoException): FileSystemProviderError {
+        if (error instanceof FileSystemProviderError) {
+            return error; // avoid double conversion
+        }
+
+        let code: FileSystemProviderErrorCode;
+        switch (error.code) {
+            case 'ENOENT':
+                code = FileSystemProviderErrorCode.FileNotFound;
+                break;
+            case 'EISDIR':
+                code = FileSystemProviderErrorCode.FileIsADirectory;
+                break;
+            case 'ENOTDIR':
+                code = FileSystemProviderErrorCode.FileNotADirectory;
+                break;
+            case 'EEXIST':
+                code = FileSystemProviderErrorCode.FileExists;
+                break;
+            case 'EPERM':
+            case 'EACCES':
+                code = FileSystemProviderErrorCode.NoPermissions;
+                break;
+            default:
+                code = FileSystemProviderErrorCode.Unknown;
+        }
+
+        return createFileSystemProviderError(error, code);
+    }
+
+    // #endregion
+
+    dispose(): void {
+        this.toDispose.dispose();
+    }
+}